The present invention relates to writing instruments capable of self illumination. More specifically, the present invention relates to a pen, marker, or highlighter with an electrically powered source of illumination contained within the device. The present invention even more specifically relates to a highlighter marker that has a powered light source, the light being guided towards the central axis of an ink reservoir containing a collection of ink, and preferably a flourescent ink. The ink will luminesce, glow, and emit light when the light source is switched on. The present invention also relates to a method of advertising by providing a consumer or a business with a writing instrument capable of illuminating an ink reservoir.
There are several varieties of writing instruments. Highlighting markers are also well known in the prior art. Typically, these specialized markers are utilized, for example, by students to mark important text in a book, or by office personnel and professionals to mark important parts of documents. Over the years, several ink colors have become available besides the customary yellow markers. More recently, fluorescent highlighting ink has been available as a choice to the consumer. Furthermore, some manufacturers of highlighter markers have utilized a clear ink reservoir as part of a writing instrument body in order to display the ink remaining within the reservoir and to make the writing instrument more interesting in appearance. These markers with a clear ink reservoir have become very popular.
Combining a writing instrument with a light source is also well known in the art. The motivation to do so is usually to provide light for the user of the instrument to see a writing surface in a darkened room. However, lights have also been combined with pens to provide either an interesting visual effect or to bring advertising to the attention of a consumer. In the prior art, only the exterior of the writing instrument has been illuminated. The prior art, in fact, teaches away from directing light into an ink reservoir.
U.S. Pat. No. 6,164,856 to Lo discloses a lighted pen in which logos on a transparent body and the pen tip are illuminated by means of a light source and a convex circular cylindrical optical lens. The writing implement has a built-in illumination system that includes a pen-top, a translucent pen-body, and a translucent pen-tip. A battery, an electrical switch and a lamp are housed within the pen-top. A convex circularly cylindrical optical lens is positioned between said lamp and said marking element so that light from the lamp is diverted away from the central axis of the pen, towards the peripherally translucent pen-body. The light then propagates along the periphery of the pen to the pen-tip. As a result of the lens, printed information located on the pen-body is illuminated, as well as a region located immediately adjacent to the pen-tip. In this patent, the pen ink itself is not illuminated and this patent teaches away from directing light down the center axis into an ink reservoir.
U.S. Pat. No. 5,405,208 to Hsieh discloses a pen with illuminating function. A switch assembly is disposed in an upper end of the upper pen sleeve, whereby a circuit is opened or closed to turn on or off a bulb or LED located at the pen tip. The pen provides an illuminating effect for the user to write in a dim place while enabling the user to write without obstruction. In this patent, the pen ink is not illuminated and the LED is in the very tip of the writing end of the pen.
U.S. Pat. No. 6,238,057 to Chen discloses a combination light pen, wherein the lower barrel comprises a water chamber disposed around an ink cartridge, with display items floating inside the water chamber. Light from an LED passes through the items in the water chamber and illuminates them. Here, the illuminated chamber contains water and does not contain ink. The ink cartridge is isolated from the illumination. Also, there is no light conductive member directing the path of the light towards the central axis of the pen. Finally, the liquid in the illuminated chamber is not fluorescent.
U.S. Pat. No. 6,299,372 to Wang discloses an advertising effect photo pen. The front tube of the pen is a hollow transparent material and a refill is connected at a front end. The surface of the front tube is formed with a transparent surface and a shielding surface and the shielding surface or the transparent surface has advertise patterns. When the user touches a light emitting unit, the transparent surface and the surface of the front tube will light up to present an advertise effect. The light is not directed through the ink and the ink does not glow or light up.
Other patents disclosing illuminating pens with a switched light source are U.S. Pat. Nos. 6,439,735; 6,390,641; 6,129,473; 6,099,185; 5,803,583; 5,470,164; 5,143,465; 4,518,274. None of these patents teach the desirability of guiding the light emitted from a light source directly into the ink chamber. Directing light down the central axis of an ink reservoir is not disclosed in the prior art. Moreover, the prior art teaches away from directing light down the central axis of a writing instrument. Furthermore, none of these patents teach using a light source to illuminate ink, and more specifically a flourescent ink, in combination with a writing instrument.